Abstract
Measurements of plankton community composition (eight planktonic groups), particle size-fractionated (10, 20, 53, 70, and 100-μm Nitex screens) distributions of organic carbon (OC) and 234Th, and particle export of OC and 234Th are reported over a seasonal cycle (2006–2007) from the Bermuda Atlantic Time-Series (BATS) site. Results indicate a convergence of the particle size distributions of OC and 234Th during the winter-spring bloom period (January–March, 2007). The observed convergence of these particle size distributions is directly correlated to the depth-integrated abundance of autotrophic pico-eukaryotes (r = 0.97, P < 0.05) and, to a lesser extent, Synechococcus (r = 0.85, P < 0.14). In addition, there are positive correlations between the sediment trap flux of OC and 234Th at 150 m and the depth-integrated abundance of pico-eukaryotes (r = 0.94, P < 0.06 for OC, and r = 0.98, P < 0.05 for 234Th) and Synechococcus (r = 0.95, P < 0.05 for OC, and r = 0.94, P < 0.06 for 234Th). An implication of these observations and recent modeling studies (Richardson and Jackson, 2007) is that, although small in size, pico-plankton may influence large particle export from the surface waters of the subtropical Atlantic.
Recommended Citation
Brew, H. S., S. B. Moran, M. W. Lomas, and A. B. Burd. 2009. "Plankton community composition, organic carbon and thorium-234 particle size distributions, and particle export in the Sargasso Sea." Journal of Marine Research 67, (6). https://elischolar.library.yale.edu/journal_of_marine_research/253